A Johnson & Johnson internal analysis of its recalled hip implants showed the all-metal devices could fail within five years for nearly half the patients who had received them, The New York Times reports.

The document from 2011 was unsealed last week by a judge in Los Angeles as part of a lawsuit brought by a patient against the DePuy Orthopaedics unit of New Brunswick-based J&J. More than 10,0000 lawsuits have already been filed against DePuy by patients who received the Articular Surface Replacement, or A.S.R.